Both inbound and outbound LDP label binding filtering are supported.
Inbound filtering is performed by way of the configuration of an import policy to control the label bindings an LSR accepts from its peers. Label bindings can be filtered based on:
prefix-list (match on bindings with the specified prefix/prefixes)
neighbor (match on bindings received from the specified peer)
The default import policy is to accept all FECs received from peers.
Outbound filtering is performed by way of the configuration of an export policy. The Global LDP export policy can be used to explicitly originate label bindings for local interfaces. The Global LDP export policy does not filter out or stop propagation of any FEC received from neighbors. Use the LDP peer export prefix policy for this purpose.
By default, the system does not interpret the presence or absence of the system IP in global policies, and as a result always exports a FEC for that system IP. The consider-system-ip-in-gep command causes the system to interpret the presence or absence of the system IP in global export policies in the same way as it does for the IP addresses of other interfaces.
Export policy enables configuration of a policy to advertise label bindings based on:
direct (all local subnets)
prefix-list (match on bindings with the specified prefix or prefixes)
The default export policy is to originate label bindings for system address only and to propagate all FECs received from other LDP peers.
Finally, the 'neighbor interface' statement inside a global import policy is not considered by LDP.